linux high order Nginx reverse proxy
Nginx reverse proxy function Reverse proxy: reverse proxy is also called reverse proxy. It refers to a way to proxy the request of the external netwo...
Flink asynchronous contradiction - sharp Async I/O
Dimension table JOIN - a business scenario that cannot be bypassed In the process of Flink flow processing, it is often necessary to interact with ext...
OOM problems caused by a MongoDB paging query
OOM Description: 2018-09-18 14:46:54.338 [http-nio-8099-exec-8] ERROR o.a.c.c.C.[.[.[.[dispatcherServlet] - Servlet.service() for servlet [dispatcherS...
Storm profile format exception
Storm's configuration file format is prone to errors, which causes Storm to fail to start correctly. The error messages caused by the format are...
[drain pit] Ftp normally connects to the server but cannot get the file
Some codes in ftp tool class ftp util are as follows: import org.apache.commons.net.ftp.*; public class FtpUtil { private static Logger log = Logger.g...
Talk about registerConsumer and unregisterConsumer of rocketmq
order This paper mainly studies the registerConsumer and unregisterConsumer of rocketmq. MQClientInstance rocketmq-client-4.5.2-sources.jar!/org/apach...
Weather forecast microservice: build spring cloud microservice from 0
As usual Project github link This project realizes the process of transforming a simple weather forecast system into a spring cloud microservice syste...
org.springframework.web.multipart.MaxUploadSizeExceededException
The company assigned me a task to do the second phase development of a project. After taking over from other project teams, the test files are upload...
MLlib basic data type
MLlib uses vectors as its localized storage type, which are mainly composed of two types: sparse and dense Code: import org.apache.spark.mllib.linalg...
Some pits of Object to Map
Here, three methods of Object mapping are summarized 1. Use reflection getDeclaredFields and getFields /** * Clean the data of the incoming object, re...
Saltstack user guide 03 configuration management
1. Host planning Matters needing attention If the configuration file of master or minion is modified, the corresponding service must be restarted. 2....
mybatis automatically fills in the time field
For the created ﹣ on and updated ﹣ on entities, it is unnecessary for developers to intervene, because it is enough to explain the use scenario, that ...
java instance understands the concept of blockchain
The core of blockchain is decentralized storage. Traditional database solutions, including relational database and non relational database, belong to...
Spring Boot 2.x Actual StateMachine
This article was first published on a personal website: Spring Boot 2.x Actual StateMachine Spring StateMachine is a state machine framework. In the S...
Comparison of java replication methods
1. Background In the actual programming process, we often encounter this situation: there is an object A, at A certain time A already contains some va...
Mybaits Source Parsing - The most detailed network, none: ResultSet automatically maps to entity class objects (last)
In the previous article, we sent SQL to the database and returned a ResultSet. Next, we automatically mapped the ResultSet to an entity class object.T...
Are you still copying object properties with BeanUtils?
When doing business, in order to isolate changes, we will separate DO queried by DAO from DTO provided by front end. About 90% of the time, their stru...
Apache Web page and security optimization in Linux system
Apache Web page optimization Apache Web page optimization overview In an enterprise, only the default configuration parameters are used after Apache ...
Installation of HBase on Centos7 and configuration of Eclipse+Maven
I. configuration process of Eclipse+Maven 1. Install and configure JDK Configure the JDK environment on Windows 2. Install Eclipse 3. Install Maven E...
Flink getting started state update
There is such a need to count the number of times a line is clicked every hour, It needs to write statistics to redis every 30 seconds, and use the S...
Deep optimization of apache working mode, ab stress test, apache directory attribute
ab pressure test Apache has its own stress testing tool ab, which is simple and easy to use. It can simulate various conditions to make a test reques...
Shell script Basics
Bowen catalogueI. Shell script FoundationRedirection and pipeline operation3. Use Shell variable I. Shell script Foundation Shell script in Linux sys...
Hibernate 4 + MySQL demonstration of Chinese naming
Recently, there is an opportunity to verify the feasibility of Chinese naming in a given development environment. The source code of the example is as...
Configure Maven 3.6 and Springboot to build Java Web projects
The latest Maven 3.6 build Java Web project in conjunction with Spring boot is very convenient, just download Maven 3.6 to start building. First, mak...
Synchronizer for Java Multithread Programming
Synchronizer Solutions are provided for each specific synchronization problem Semaphore Semaphore controls access to shared resources through counters...
zookeeper Pseudo-Distributed Architecture
Get the zookeeper binary package, address[ https://www.apache.org/dyn/closer.cgi/zookeeper/](https://www.apache.org/dyn/closer.cgi/zookeeper/The curr...
Some Problems Needing Attention in Linux System Security
Write on the front: When you deploy a server, the first step should not be to deploy the application, security is the first task. If one day you log o...
Configuration of Struts 2 Verification Framework and validation.xml Verification Rules
Reference resources: http://www.blogjava.net/focusJ/archive/2010/11/15/367272.html http://blog.csdn.net/hackcoder/article/details/18510337 Naming rul...
Linux-Day3-Installation Software
There are three ways to install software in Linux: 1.rpm # is equivalent to clicking on windows to install next step 2.yum # is equivalent to one-cli...
Backstage of Guge's Primary School (21) - DBUtils
Exploring the Difficulties of Android Soft Keyboard Deep Exploration of Android Asynchronous Essence Handler Detailing the indispensable cornerstones...